Best Available Techniques
Code of Practice
In such instances, it may be sufficient for a short, evidence based, report to be produced
comparing the advantages and disadvantages of any alternative technologies and/or
management practices compared to those currently in use, together with a defensible
argument for any improvements that will, or will not, be implemented following the study.
In many cases, qualitative assessments will represent a proportionate approach, reflecting
the level of information available and avoiding a false impression of accuracy within the
decision making process. Nonetheless, such an approach must be reasoned, logical and
transparent. It must contain sufficient information to allow a fully informed independent
review to be undertaken.
5.7.2 Quantitative Assessments
There are two basic approaches to quantitative assessment which can be used individually
or in combination, these are Cost Benefit Analysis (CBA) or Multi Attribute Analysis (MAA)
(see Appendices 2 and 3). Both approaches are equally valid for demonstrating BAT and
have their own advantages and disadvantages as follows.
Advantages and disadvantages of CBA and MAA assessment approaches
Allows direct comparisons
between different studies.
Fixed evaluation criteria means
study work is focussed on content
rather than process.
Assessment methodology and
means of evaluation is
transparent to stakeholders.
Provides means of understanding
Because evaluation scale is
money, scale is not capped.
Often confused with cost analysis which
undermines stakeholder confidence in
Need to get agreement on how benefits
and detriments are valued.
Perceived as requiring large amounts of
detailed underpinning information and
onerous to apply.
Monetorisation of less tangible costs
and benefits may be open to challenge.
Perceived as lacking transparency due
to failure to provide sufficient
breakdown of numbers.
Stakeholders can feel disenfranchised
as they cannot substantially influence
Helps build stakeholder support
to outcome as they get to set the
Stakeholders are comfortable with
the process as routinely used in
Lack of fixed criteria and values means
cannot readily compare outcomes from
different studies or determine
proportionality of outcome
Process can be heavily influenced by
study attendees and individual bias
Time consuming to agree scoring
process and criteria
Difficult to avoid double counting
between evaluation criteria
Seen as an excuse for not having
Outputs often not readily transparent to
those outside of study group
Need to understand how scores relate
to a real world perspective.
It is worth noting that:
• Neither MAA or CBA can take account of all the factors relevant to a decision and
therefore in making a decision it is also important that less tangible socio political